The candidate's long-term goals include: 1) testing and refining two theoretical models to explain the psychophysiological effects of anxiety and pain in labor and the effectiveness of hydrotherapy, and 2) gaining consultation and collaboration with other researchers and students using physiological measurement techniques in the laboratory and clinical settings. Immediate goals are to increase knowledge and skill in: (1) physiology, including general, neural/hormonal, and immersion; (2) physiological instrumentation, including radioimmunoassay (RIA), immunoenzymatic assay (EIA), high performance liquid chromatography (HPLC) and electromyography (EMG); (3) statistics, both general and repeated measures; and (4) professional growth, including preparation of manuscripts and grants, with the goal of becoming an independent scientist. The effects of intervention with hydrotherapy in labor are poorly understood though use has escalated. The proposed study will focus on the psychophysiological effects of hydrotherapy during labor and the physiological indicators of sympathetic nervous system and adrenocortical inhibition associated with immersion and the relaxation response. Using a repeated measures correlational design, data will be gathered from 15 healthy patients, immersed to the xiphoid in 37 degrees C water for 1 hour. Data will be collected prior to and at 15 and 45 minutes of hydrotherapy. Visual analogue scales (VAS) will measure anxiety and pain; physiological measures will include plasma catecholamines, cortisol, beta endorphin, oxytocin, plasma volume shift, and uterine contractility, and will be analyzed using HPLC, EIA, RIA, hemoglobin (HGB) and hematocrit (HCT), and abdominal EMG respectively. Statistical analyses will include a one-way within-subjects analysis of variance and Pearson r technique. While these physiological measures, excluding plasma volume shift, have not been previously used to study hydrotherapy in labor, it is anticipated that post intervention measures will reflect a decrease in parturient anxiety and pain, as will subjective measures.